Numbers beginning with 626-831

Pasadena, a city in Los Angeles County, California, United States. As of 2010 United States Census, the population of Pasadena was 137,122, making it the 180th-largest city in the United States, down from 168th place in 2009. Pasadena is the ninth-largest city in Los Angeles County, and on June 19, 1886, became the fifth to be incorporated in Los Angeles County, after Los Angeles (April 4, 1850), Anaheim (February 10, 1870) and Santa Ana (June 1, 1886); the latter two moved to Orange County after its separation from Los Angeles County in 1889. It is one of the primary cultural centers of the San Gabriel Valley. source

Area code 626 is a California telephone area code that was split from area code 818 on June 14, 1997. It covers most of the San Gabriel Valley and nearby areas in the northeastern portion of Los Angeles County, California, U.S., including Arcadia, Monrovia, El Monte, most of Pasadena and West Covina. source